Yda and Moenbryda questions [spoilers]

[Maiandra]

According to Y'shtola, they all knew and were just humoring her because they understood that she still needed her sister. It isn't specified who "all" includes, but if Moenbryda was that close, then she would've recognized, too. Still, Lyse was with Yda when she joined the Archons, so they both could've been just as close.

"We all recognized you at once. 'Twas Papalymo that persuaded us to maintain the charade."

Regardless, I've also wondered if the writers "knew" who she was all along, or if it was just something they came up with later, when they decided to write the character off.